Objective Antitumour treatment in the last 2 weeks of death (ATT-W2) and a new regimen of ATT within 30 days of death (NATT-M1) are considered as aggressive end-of-life (EOL) care. We aimed to assess factors associated with inappropriate use of antitumour treatment (ATT) at EOL. Methods Data of patients with cancer who died in 2013, 2015, 2017 and 2019 in a single for-profit cancer centre were retrospectively analysed. ATT was divided into chemotherapy (CT), oral targeted therapy (OTT), hormonotherapy and immunotherapy (IMT). Results A total of 1282 patients were included. NATT-M1 was given to 197 (15.37%) patients, and 167 (13.03%) had an ATT-W2. Patients with a performance status of <2 and treated with CT had more both ATT- W2 (OR=2.45, 95% CI 1.65 to 3.65, and OR=10.29, 95% CI 4.70 to 22.6, respectively) and NATT-M1 (OR=2.01, 95% CI 1.40 to 2.90, and OR=8.41, 95% CI 4.46 to 15.86). Predictive factors of a higher rate of ATT-W2 were treatment with OTT (OR=19.08, 95% CI 7.12 to 51.07), follow-up by a medical oncologist (OR=1.49, 95% CI 1.03 to 2.17), miscellaneous cancer (OR=3.50, 95% CI 1.13 to 10.85) and length of hospital stay before death of <13 days (OR=1.92, 95% CI 1.32 to 2.79). Urinary tract and male genital cancers received less ATT-W2 (OR=0.38, 95% CI 0.16 to 0.89, and OR=0.40, 95% CI 0.16 to 0.99) and patients treated by IMT or with age <69 years more NATT-M1 (OR=19.21, 95% CI 7.55 to 48.8, and OR=1.69, 95% CI 1.20 to 2.37). Patients followed up by the palliative care team (PCT) had fewer ATT-W2 and NATT-M1 (OR=0.49, 95% CI 0.35 to 0.71, and OR=0.42, 95% CI 0.30 to 0.58). Conclusions Most recent ATT and access to a PCT follow-up are the two most important potentially modifiable factors associated with aggressive EOL in patients with cancer. Early integrated palliative oncology care could help to decrease futile ATT at EOL.